Khan.scratchpad.disable(); Vanessa sells magazine subscriptions and earns $$10$ for every new subscriber she signs up. Vanessa also earns a $$37$ weekly bonus regardless of how many magazine subscriptions she sells. If Vanessa wants to earn at least $$72$ this week, what is the minimum number of subscriptions she needs to sell?
Solution: To solve this, let's set up an expression to show how much money Vanessa will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Vanessa wants to make at least $$72$ this week, we can turn this into an inequality. Amount earned this week $\geq $72$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $72$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $10 + $37 \geq $72$ $ x \cdot $10 \geq $72 - $37 $ $ x \cdot $10 \geq $35 $ $x \geq \dfrac{35}{10} \approx 3.50$ Since Vanessa cannot sell parts of subscriptions, we round $3.50$ up to $4$ Vanessa must sell at least 4 subscriptions this week.